What are the reasons for the engine's failure to start when cold?
2 Answers
Reasons for the engine's failure to start when cold: 1. Low engine temperature; 2. Excessive carbon buildup on valves and intake ports causing difficulty in cold starts; 3. Faulty water temperature sensor; 4. Battery depletion or expired battery lifespan; 5. Incorrect oil grade used; 6. Starter motor speed not meeting requirements; 7. Insufficient cylinder compression pressure in the engine. Precautions for cold starts in winter: 1. If the vehicle is parked without a heated garage, it is recommended to park it in a sheltered position, avoiding windy areas; 2. Before starting, turn on the ignition switch for about 5 to 8 seconds to ensure sufficient fuel supply for easier engine starting; 3. For manual transmission vehicles, depress the clutch during startup to separate the engine from the transmission, reducing engine resistance.
As someone who frequently tinkers with cars, I believe the core issues of cold-start failures mostly lie in the battery and electrical circuits. Low temperatures can reduce battery capacity, especially for older batteries—when the charge is insufficient, it simply can't power the starter motor. Another factor is the starter itself; if the gears are worn or the solenoid fails, turning the key might only produce a clicking sound with no response. Another common issue relates to the fuel system, such as the fuel pump struggling in cold weather or clogged fuel injectors due to carbon buildup affecting gasoline injection. I recommend first trying a jump-start or replacing the battery. If the problem persists, check for starter motor sounds. Also, don’t overlook the spark plugs and ignition coils—these components have limited lifespans, and excessive carbon buildup can make cold starts difficult. Regular maintenance of these parts and warming up the car for a few minutes in winter can help avoid such troubles.
